There are delays on all routes to and from London Waterloo rail station, and disruption is set to last all day, due to a points problem.
Platform 1 has been closed at the station, meaning services may be cancelled or revised, National Rail said.
South Western Railway have been advised that a set of points outside platform one at London Waterloo are defective, the rail operator said.
Their engineers are aware, however, the nature of the fault means engineers are unable to fix the problem until close of service this evening.
They are continually working on a service plan to ensure disruption is kept to a minimum during the day and more essentially during the morning and evening peak. To reduce the delays to trains, some services may have to be altered or revised at short notice.
Meanwhile, the delays are occurring at the same time as industrial action by the RMT union, which is affecting Southern services. Although Southern said it would run a normal service "on most routes", there will be some alterations.
Southern trains to and from Guildford will not run, putting pressure on South Western Railway which is affected by the platform closure at Waterloo.
|The following alterations will occur to services travelling to London Waterloo:|